That looks more complicated than the kit I have. Mine is just sides, top and bottom, baffle and two braces in the center section. Yours appears to have an inner structure.
I haven't built mine yet as I'm waiting on replacement baffles, as the guy cut the holes incorrectly.
Are you going to run a plate amp per side? I've got all of them on one, which actually works, though I don't think it's recommended.
Think you're gonna be really happy w/ this setup.